| EARTHQUAKE |  The surface that we walk on appears hard, almost rock-solid. However, Earth's surface is, in fact, not a stationary layer of soil. It is made up slowly moving sections. In other words, they are dynamic. These sections are called tectonic plates. Tectonic plates are, thankfully, lazy and could give snails a complex. As a result, their movement can be detected only on geological time-scales. If you trawl the Internet a bit and research, you will discover that North America and Europe -- to give tectonic plates names of continents -- are drifting apart at the rate of five centimeters per year. This ultra-slow motion, nevertheless, builds up enormous stress in the crust. If stress levels soar beyond a certain threshold, a portion of the crust will implode, moving suddenly and, often times, violently. This sudden movement occurs along a fracture called the 'fault zone', where the earth's crust is weak. And that is an earthquake . |
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 Explanation
The scale for measuring earthquakes was first developed by geologist Charles Richter at the California Institute of Technology in the 1930s. The Richter Scale, which gives us the intensity of an earthquake, is named after him. However, the Richter scale is only one of the several methods that seismologists use. However, it has become famous because it gives an easily understandable number, called the magnitude, to an earthquake. The bigger the number, the more devastating the quake. Therefore, a quake measuring 4.0 on the Richter scale is okay, no great shakes. However, a 6.0 is dangerous, and anything above 7.0 is, to put it simply, disastrous. A seismograph is what indicates this magnitude. It keeps drawing a line on a paper, the line representing movement of the earth's crust. Its other end is inserted deep into the layers of the earth. In some ways, a seismograph looks like angiogram or any other medical graph you get to see on computer monitors used in the hospital scenes in movies. Generally, it is a straight line. However, if there is an earthquake, there are violent-looking deviations on the graph. There are no lower and upper limits on a Richter scale, only a "logarithmic" rhythm. Meaning: each one-point represents a 10-fold increase in the magnitude (read power) of the quake. A tremendous amount of energy is released; the amount increases with the intensity of the quake. The rate at which the energy is released rises by a factor of 32 for each one-point increase in the magnitude of the quake. The "7+" earthquakes release so much energy that man-made explosions cannot even begin to match it. In 1906, San Francisco was rocked by a quake measuring 8.3; its power was enough to destroy one million Hiroshima’s. The worst quake in human history measured 9 on the Richter scale. On the surface, stretching over thousands of kilometers, people may be blissfully unaware that, beneath their feet, two huge blocks of earth (tectonic plates) are inching towards each other. In addition, somewhere on the surface, unmarked, are the boundaries of these places. The people or places located on these boundaries face the maximum risk at the time of The Deadliest Kiss. Well-known tectonic boundaries on Planet Earth are the edges of the Pacific plate, which lies beneath the Pacific Ocean. This plate is relatively hyperactive, which explains the frequent earthquakes along the west coast of North America and in Alaska, Chile and Japan. It is also known to cause volcanic eruptions in northwest US, the Andes Mountains and the Philippines. |  |
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